The latest supposedly leaked iPhone 5 part is a tray for a nano-Sim card. We're skeptical about the authenticity of the images from Nowhereelse.fr, but there's plenty of reason to believe that Apple will use an even tinier SIM on its next-gen iPhone. Who cares? It turns out a little SIM could be a big deal.

Apple designed the new nano-SIM, and fought hard for its acceptance, so it's pretty safe bet that the tech will end up on the new iPhone. On the upside, the new SIM is 40-percent smaller than its predecessor, which would allow the new iPhone's design to be slimmer than before. Slimmer and smaller is a hard design decision to argue against even if the majority of smartphones released by Apple's competition are getting bigger every year. Even if you're into big phones, the, a smaller SIM card means that Apple—and everyone else—can cram more of something else inside.

But new hardware always comes with drawbacks. The nano-SIM switch creates all sorts of compatibility problems. One of the great features of SIM technology is that it allows you to easily switch from one phone to the next. When the industry switched to micro-SIM, at least you could use a clunky adapter to switch to older phones, but the new SIM design makes that a much more challenging problem than before. What's more, if you've tried to use a micro-SIM with an adapter in an iPhone 3G, you know the cards get stuck. And what about all of the people who buy iPhones on the secondary market? Switching a SIM card over isn't the end of the world, but it's a pain.

Sometimes Apple pushes infuriating new hardware like the rumored 19-pin dock connector because it's for your own good. SIM-card technology is supposed to make our lives easier, and in the short term, the switch to nano-SIM will make things more complicated. While there's no clear technological reason for a SIM to be smaller, the case for thinner—or more hardware—packed-devices is a strong one. [Nowhereelse.fr via 9To5Mac]